Setting apparatus for blind rivets or the like

ABSTRACT

A setting apparatus  30  in which a mandrel of a blind rivet is inserted into a hole  47  of a nose at the front end of the setting apparatus, and wherein a rivet body of the rivet is projected from the nose into a mounting hole of a workpiece. The mandrel is pulled rearward of the nose with a force capable of breaking the mandrel and expanding a shank of the rivet body so that the rivet is set in the workpiece by the expanded shank and a flange of the rivet body, followed by discharging of the broken mandrel from the setting apparatus. The force for pulling the mandrel is obtained from hydraulic pressure of a hydraulic cylinder  34 . The hydraulic pressure is produced by a piston  41  which moves in a pneumatic cylinder  39  adjacent to the hydraulic cylinder. The nose  31  is axially aligned with an apparatus body  33  including the hydraulic cylinder and the pneumatic cylinder  39  along the longitudinal direction of the setting apparatus  30  from the front end to the rear end thereof. A discharge path for the broken mandrel is formed  5  by a hollow tube extending from the mandrel inserting hole  47  of the nose through (tubes  49  and  50  of) the apparatus body and (a tube  51  of) the hydraulic cylinder to the rear end  53  of the setting apparatus.

BACKGROUND OF THE INVENTION

The present invention relates to a setting apparatus for fasteners ofthe type in which during setting a blind rivet, lock bolt or the like amandrel thereof is broken. More specifically, the present inventionrelates to a setting apparatus for blind rivets which includes amechanism for discharging the broken mandrel from a nose of the settingapparatus through the inside thereof and is suitable for inserting andsetting a blind rivet into a workpiece from the position above theworkpiece.

A fastener such as a blind rivet or a lock bolt has been well knownwhich comprises a hollow rivet body and a mandrel inserted into thisrivet body. Generally, a hydraulic actuated setting apparatus is used ina setting operation for setting the fastener in a workpiece. The settingapparatus is provided with a jaw at a nose defined by the front end ofthe apparatus to hold the mandrel of the blind rivet. When the mandrelof the blind rivet is inserted into the nose to hold the mandrel withthe jaw, while a rivet body of the blind rivet will be projecting fromthe nose into a mounting hole of the workpiece. When the settingapparatus is triggered, a piston of a pneumatic cylinder is actuated andthen this piston is slidably moved in a hydraulic cylinder to produce ahigh hydraulic pressure. Then, by this hydraulic pressure, the jaw isdriven within the setting apparatus in a pull-in direction for pullingthe mandrel strongly enough to break or fracture the mandrel at adesired breakable position and to expand a shank of the rivet body sothat the rivet body is set in the workpiece by the expanded shank and aflange of the rivet body. The broken mandrel is released from the jaw,and then transferred in the setting apparatus from the front end to therear end thereof,whereafter the broken mandrel is discharging from therear end of the setting apparatus or collected by a broken mandrelcollecting vessel provided at the rear end of the setting apparatus.

One type of well known conventional blind rivet setting apparatus isdisclosed in U.S. Pat. No. 3,898,833. In this type of setting apparatus,a handle with a trigger extends to intersect with an apparatus bodyextending rearward from a nose of the setting apparatus. This mayprovide a convenient configuration for being gripped by an operator andmay serve various uses. However, this setting apparatus is not suited tothe operation for inserting and setting a blind rivet into and in aworkpiece from the position above the workpiece in the position higherthan the waist position of an operator. This is because when the frontend of the setting apparatus is placed on the workpiece located in aposition higher than the waist position of the operator from theposition above the workpiece, the operator is forced to grip the handlein an unnatural manner, resulting in unpractical operation performance.A setting apparatus suitable for inserting and setting a blind rivetinto and in a workpiece from the position above the workpiece.

One example of such a prior art apparatus is shown in FIGS. 1 and 2. InFIG. 1, the setting apparatus I comprises a nose 2, an apparatus body 3extending rearward (upward in the figure) from the nose 2, and apneumatic cylinder 5 extending further rearward from the apparatus body3. A hydraulic cylinder is provided inside of the apparatus body 3 at aposition adjacent to the pneumatic cylinder 5. The setting apparatus 1is formed to extend longitudinally from the nose 2 to the pneumaticcylinder 5 in totality. The apparatus body 3 of the setting apparatus 1is provided with a handle 6 having a trigger lever 7 attached thereto.An operator may carry out a setting operation of a fastener (not shown)such as a blind rivet from the position above a workpiece by grippingthe apparatus body 3 having the handle 6 and directing the nose 2 of thesetting apparatus 1 downward. A hanging member 9 is attached to theapparatus body 3 of the setting apparatus 1. As shown in FIG. 2, thehanging member 9 is supported by a power-assist arm 13 to which a crosspiece 11 of a supporting post 10 is mounted. Thus, the power-assist arm13 bears a weight corresponding to that of the setting apparatus 1 toallow load applied to hands of the operator to be reduced and thereby tofacilitate the setting operation. A compressed air supply pipe 14 iscoupled to the setting apparatus 1. By gripping the trigger lever 7 ofthe handle 6, compressed air may be introduced into the pneumaticcylinder 5, the operation of which will compress oil in an adjacenthydraulic cylinder to carry out the setting operation, as described andshown hereinafter.

In the vertical type setting apparatus 1 extending longitudinally asshown in FIGS. 1 and 2, a pneumatic cylinder 5 is provided above therear end (i.e. upper end) of the apparatus body 3, and has no handleintersecting with the apparatus body. Thus, the apparatus may be reducedin size and weight, and is suited to the operation for inserting andsetting a blind rivet into and in a workpiece from the position abovethe workpiece, which position may be higher than the waist position ofan operator. However, since the pneumatic cylinder having a largediameter is provided at the rear end or the upper end of the apparatus,the mandrel broken by the pull-action of the jaw is required to getaround the pneumatic cylinder 5 in order to be discharged at the rearend of the setting apparatus 1. This is possible by providing a curvedbroken mandrel discharge path. The broken mandrel discharge path isdefined by the reference number 15 in FIGS. 1 and 2. FIG. 3 shows astate in which this broken mandrel discharge path 15 is curved in anarea where the path comes out of the apparatus body 3. In FIG. 3, thebroken mandrel discharge path 15 is curved in the area 16. If aprecedent broken mandrel is jammed in this curved area 16 a and asubsequently broken mandrel is provided, the path can be undesirablyclogged by the conjuncture between the broken mandrels 18A and 18B shownby dotted lines in FIG. 3.

Another type of prior art blind rivet setting apparatus, different fromthe setting apparatus 1 shown in FIGS. 1 to 3, is shown in FIG. 4, wherethere is another setting apparatus 1A in which a nose 2 and apparatusbody 3, and a pneumatic cylinder 17 are provided in the longitudinaldirection of the setting apparatus with offsetting their axesrespectively. In this setting apparatus 18, when a compressed air issupplied to an upper end of a piston 19 of a pneumatic cylinder 17 tomove a piston rod 21 into an oil sump 22, the resulting compressed oilis supplied to a hydraulic cylinder 23 provided inside of the apparatusbody 3. Then, a hydraulic piston 25 is moved upward to pull up a jaw 26disposed in the front end of the nose 2. This pull-up force is strongenough to break the mandrel of the fastener held by the jaw 26. In thissetting apparatus 18, the broken mandrel can be discharged from an exit27 through a hollow tube formed at the center of the nose 2 whichreceives therein a hollow tube of the hydraulic piston 25 shiftablymounted in the apparatus body 3, and thus this discharge path isstraight and not curved. This is because the axis of the pneumaticcylinder 17 is offset from the nose 2 and apparatus body 3 and therebythe path is not required to go around the pneumatic cylinder 17.However, this pneumatic cylinder 17 having the axis offset from the nose2 and the apparatus body 3 leads to a large setting apparatus andheavier setting apparatus as a whole. Thus, this setting apparatus maynot be well suited to the operation of inserting and setting a blindrivet into and in a workpiece from the position above the workpiece orin the position higher than the waist position of an operator.

SUMMARY OF THE INVENTION

Thus, in a setting apparatus for blind rivets of the type in whichsetting is achieved by breaking a mandrel of a blind rivet, it is anobject of the present invention to provide a compact and lightweightsetting apparatus capable of discharging the resulting broken mandrelwithout any jamming.

In order to achieve the above object, the present invention provides asetting apparatus for blind rivets, constructed such that a mandrel of afastener is inserted into a hole of a nose at the front end of thesetting apparatus, and while a rivet body of the fastener is projectedfrom the nose into a mounting hole of a workpiece, the mandrel is pulledrearward of the nose with a force capable of breaking the mandrel toexpand a shank of the rivet body so that the fastener is set onto theworkpiece by the expanded shank and a flange of the rivet body, followedby discharging the broken mandrel out of the setting apparatus, whereinthe force for pulling the mandrel is obtained from hydraulic pressure ofa hydraulic cylinder, the hydraulic pressure being produced by a pistonwhich moves in a pneumatic cylinder adjacent to the hydraulic cylinder.The setting apparatus has the nose thereof aligned with the apparatusbody which includes the hydraulic cylinder and the pneumatic cylinderaligned in the longitudinal direction from the front end to the rear endthereof, and a discharge path for the broken mandrel is formed by ahollow tube extending from the mandrel insertion hole at the nosethrough the apparatus body and the hydraulic cylinder to the rear end ofthe setting apparatus.

In the aforementioned setting apparatus, the construction in which thenose is arranged with the apparatus body including the hydrauliccylinder and the pneumatic cylinder along the longitudinal direction ofthe setting apparatus allows the setting apparatus to be reduced in sizeand weight. Further, since the broken mandrel discharge path extendsfrom the nose through the apparatus body and the pneumatic cylinder tothe rear end of the setting apparatus, the discharge path need not becurved. Thus, the broken mandrel may smoothly pass through the dischargepath and may be discharged from the setting apparatus without anyjamming in the path. Furthermore, arranging the exit of the dischargepath at the rear end of the setting apparatus allows an air hose forsupplying a compressed air and a hose for discharging the mandrel to beconcentrated at the rear end or upper end of the setting apparatus. Thisprovides easy arrangement of such hoses.

In the aforementioned setting apparatus, the broken mandrel dischargetube preferably extends linearly in the longitudinal direction of thesetting apparatus. A mandrel collecting device may be attached to amandrel discharge port of the broken mandrel discharge tube at the rearend of the setting apparatus.

As described above, according to the present invention, arranging thenose, the apparatus body including the hydraulic cylinder and thepneumatic cylinder along the longitudinal direction of the settingapparatus allows the setting apparatus to be reduced in size and weight.Further, since the broken mandrel discharge path extends from the nosethrough the apparatus body and the pneumatic cylinder to the rear end ofthe setting apparatus, the discharge path is not curved. Thus, thebroken mandrel may smoothly pass through the discharge path and may bedischarged from the setting apparatus without any jamming in the path.Furthermore, arranging the exit of the discharge path at the rear end ofthe setting apparatus allows the air hose for supplying the compressedair and the hose for discharging the mandrel to be concentrated at therear end or upper end of the setting apparatus. This provides easyarrangement of such hoses. The broken mandrel collecting device may becoupled to the broken mandrel discharge port at the rear end of thesetting apparatus. This allows the necessity for coupling the brokenmandrel discharge hose to be eliminated, and thereby provide easyarrangement of such hoses, and enhanced operation performance. Inaddition, the necessity for piping such hoses is eliminated.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

FIG. 1 is a front view of a conventional setting apparatus of the typecapable of reducing in size and weight;

FIG. 2 is a view showing a construction that the setting apparatus ofFIG. 1 is hung to use;

FIG. 3 is a partial cutaway view showing details of a broken mandreldischarge portion of the setting apparatus of FIG. 1;

FIG. 4 is a vertical sectional view of another conventional settingapparatus;

FIG. 5 is a vertical sectional view of a setting apparatus for blindrivets or the like according to a first embodiment of the presentinvention, partly cut away, wherein most of a nose and a half of a frontend of an apparatus body are omitted; and

FIG. 6 is a vertical sectional view showing the rearward of a settingapparatus according to a second embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawings, embodiments of the present inventionwill now be described. FIG. 5 shows a setting apparatus 30 forfasteners, such as blind rivets or the like, according to a firstembodiment of the present invention. In FIG. 5, a nose 31 and anapparatus body 33 of the setting apparatus 30 is similar to the nose 2and the apparatus body 3 of the setting apparatus 1A in FIG. 4. Thus, inorder to make the following explanation clear, only the front end of thenose 31 and the rear half portion (upper portion of the figure)including a hydraulic cylinder 34 of the apparatus body 33 will bedescribed and illustrated, and most of the portion of the nose 31, whilethe front half portion of the apparatus body 33 has been omitted. Sincethe setting operation of the setting apparatus 30 is also similar tothat of the setting apparatus 1A in FIG. 4, it is omitted. As needed,the description of the setting apparatus 1A in FIG. 4 may be referredto. In the setting apparatus 30, jaws 35, 35 are provided at the nose 31to hold a mandrel shank (not shown) inserted from a hole at the frontend of the nose 31. A handle 37 is provided at the apparatus body 33,and a trigger lever 38 is attached to the handle 37. In the settingapparatus 30, the axis of the nose 31 is aligned with the axis of theapparatus body 33 (and the hydraulic cylinder 34).

In the present invention, a pneumatic cylinder 39 is arranged therearward of the apparatus body 33 including the nose 31 and thehydraulic cylinder 34 in the longitudinal direction of the settingapparatus 30. A piston rod 42 of a piston 41 provided in the pneumaticcylinder 39 reciprocates in an oil sump or oil reservoir 43 in fluidcommunication with the front end of the hydraulic cylinder 34, and theoil sump 43 is arranged in parallel with the apparatus body 33. Whilethe axis of the pneumatic cylinder 39 cannot be matched with the axis ofthe nose 31 and the apparatus body 33, the present invention can providea short distance between these axes by arranging the pneumatic cylinder39 along the longitudinal direction of the setting apparatus 30. Thisallows the setting apparatus 30 to be formed in reduced size and weight.Compressed air is supplied to the pneumatic cylinder 39 from acompressed air supply section 45 through a valve 46. The valve 46 iscontrolled by the trigger lever 38. The valve 46 is opened by squeezingthe trigger lever, and thereby the compressed air is introduced into thepneumatic cylinder 39 to move the piston 41 downward in FIG. 5. Then,the piston rod 42 is moved into the oil sump 43 to supply the compressedoil to the hydraulic cylinder 33, and the jaw 35 is pulled up stronglyto break the mandrel shank.

In the present invention, the discharge path of the mandrel broken bythe jaw 35 is formed by a mandrel hole 47 on the axis of the nose 31, atube 49 and a tube 50 at the rearward thereof which are provided on theaxis of the hydraulic cylinder 34 of the apparatus body 33, a tube 51which extends through the pneumatic cylinder 39 to the rear end of thesetting apparatus 30, and a tube 55 provided at a rear end 53 of thesetting apparatus 30 and including a vacuum suction mechanism 54 for thebroken mandrel (As to the details of the action of this vacuum suctionmechanism, refer to FIG. 4). A broken mandrel discharge hose 57 iscoupled to the discharge port of the tube 55 to discharge the brokenmandrel outside in the same manner as that in FIG. 2.

As shown in FIG. 5, the broken mandrel discharge path composed of themandrel hole 47, the tubes 49, 50, 51 and 55 extends linearly on thesame axis extending in the longitudinal direction of the settingapparatus 30, and without any curve. Thus, since the broken mandrel maysmoothly pass through the discharge path and may be discharged from thesetting apparatus, the broken mandrel is never jammed in the dischargepath. Further, since the exit of the discharge path is arranged at therear end of the setting apparatus 30, the mandrel discharge hose 57 maybe attached at the rear end of the setting apparatus adjacent to thecompressed air supply section 45. Thus, the air hose coupled to thecompressed air supply section 45 and the mandrel discharge hose 57 canbe concentrated at the rear end or upper end of the setting apparatus toprovide easy arrangement of such hoses.

The hollow tube 51 penetrating through the pneumatic cylinder 39 may bemade of any suitable material capable of withstanding the pneumaticpressure in the pneumatic cylinder 39. Thus, the material is not limitedto metal, and may be plastic. Further, the piston 41 reciprocating inthe pneumatic cylinder is provided with a seal section 58 at a portionwhere the tube 51 penetrates through the piston 41 in order to preventthe leak of the compressed air.

FIG. 6 shows a setting apparatus 30A according to a second embodiment ofthe present invention. In this setting apparatus 30A, instead of themandrel discharge hose, a broken mandrel collecting device 59 isattached at the rear end of the setting apparatus 30A to collect thebroken mandrel. The broken mandrel collecting device 59 has a vessel 62surrounding an exit 61 of the broken mandrel discharge path of thesetting apparatus 30A and extending to extend the path so as to receivethe broken mandrel discharged from the extended path. To prevent theintertwisting of the broken mandrel, the vessel 62 is provided with abroken mandrel anti-intertwisting member 63 in the form of an elongatedrod extending within the vessel 62. This anti-intertwisting member 63can prevent the broken mandrel from intertwisting in the vessel. Asdescribed above, providing the broken mandrel collecting device 59 mayeliminate the necessity for coupling the broken mandrel discharge hose.This also provides easy arrangement of such hoses and enhanced operationperformance. In addition, the necessity for piping such hoses iseliminated.

In general, the above identified embodiments are not to be construed aslimiting the breadth of the present invention. It is understood that thepresent invention may be modified or have other alternativeconstructions that are apparent from and within the scope of the presentinvention as defined in the appended claims.

What is claimed is:
 1. An axially inline setting apparatus for setting ablind rivet in a mounting hole of a workpiece, the blind rivet having arivet body mounted on a mandrel with a breakable portion, the settingapparatus comprising: a. a nose formed on the front end of the settingapparatus and having a hole to receive and clamp the mandrel of theblind rivet therein; b. a force exerting means communicating with thenose; c. the force exerting means having pneumatic means and hydraulicmeans to coact with each other to exert force on the mandrel through thenose; d. the pneumatic means disposed in superposition to the nose; ande. a collection conduit extending internally of the pneumatic means tobe connected to the nose to receive the breakable portion of the mandreltherein to be discharged therethrough.
 2. The combination claimed inclaim 1 wherein: a. a collection device connected to the settingapparatus at the end thereof opposite the nose thereof; and b. thecollection conduit connected to terminate in the collection devicewhereby the breakable portions of the mandrel will be deposited in thecollection device.